PayPal officially unveils PayPal Here, an anticipated mobile payment solution that takes aim at Square. Leveraging a triangle-shaped dongle and mobile apps, PayPal says its offering, which it will push to its 100M+ customers, comes with a debit card that gives merchants 1% cash-back on some purchases, potentially lowering its rate to 1.7%. The news isn't helping eBay (EBAY-2.1%) shares, which remain pressured by a Credit Suisse downgrade.